Protractor



Jan. 10, 1928. 1,655,887

c. J. BAlLEY PRQTRACTOR Filed Dec. 3. 1924 f5 r. M5

W f Wg@ nation onscale 8 this will indicate that the blades have been separated to an angle ot 'of'pitehot a surface with respect to its base7 01", in other words, the amount ot ris-e of a.. surface per unit ot length on the base, in the device shown the graduations denoting the rise in inches per running base toot. For instance, it the blade 5 be separated from the blade 6 so that the arrow 18 registers with the numeral l in said table, this will denote the angle oit the blades one With respect to the other7 and representing a rise ot'one inch per running foot ot' the base.

In accordance with the provisions ol the patent statutes I have described the prin ciples of operation ot' my invention, together with the device which I now con- 'vsider to lrepresent the best embodiment thereof, but I desire tohave it understood 'that the device shown is only illustrative Vplate Leases? pivotall)Y connected7 one ot said blades hav ing a ring formed thereon, a toothed ring secured to said iirst mentioned ring, a plate on the other blade underlying and closing one side of said iirst-nientioned ring7 another plate having a bearing within the other side of said tirst-inentioned ringl and upon said toothed ring, there being cooperating graduations upon said plate and ring, and a geared connection between said and ring.

A protractor comprising two blades pivotally connected, one olf ,said blades having a ringl at its pivoted end with a toothed ring rigidly secured thereto and the other blade having a plate underlying said iii-stmentioned ring and closing one` side thereof, a pinion pivotallj,7 supported blv said underlying plate and in mesh with the teeth of said ring, a plate rotatabl)v mounted within said ring to close the opening on one side thereof, and a pinion secured to said last mentioned plate and in mesh with the tirst mentioned pinion, and there being eooperating gaduations on said plate` and ring.

3. protractor comprisingl two blades` pivotally connected, one ot said blades having a ring formed thereon with teeth on `the inner edge thereof, a plate on the other blade underlying and closing one side ol said ring, anotherplatie located on the other side o'f said ring and closing the opening thereinto, there being cooperatingl graduations upon said last mentioned Yplate and ring, and a geared connection between lsaid plate and ring.

CHARLES JEROME BAILE Y. 

